Chemical conversions employing solid catalysts are often conducted using a fixed ebullating, moving or fluidized bed of catalyst-containing particles. Also, catalyst/liquid slurry reaction systems may be utilized. See commonly assigned U.S. patent applications Ser. Nos. 070,579, 070,574 and 070,578, each filed Jul. 7, 1987, respectively. Each of these applications is incorporated in its entirety by reference herein.
Catalysts comprising one or more crystalline microporus three dimensional solid materials or CMSMs, i.e., catalysts which promote chemical reactions of molecules having selected sizes, shapes and/or transition states, include naturally occurring mineral molecular sieves and synthetic molecular sieves, together referred to as "molecular sieves," and layered clays.
Catalyst-containing particles often include one or more matrix materials, such as binders and fillers, to provide a desired property or properties to the particles. These matrix materials often promote undesirable chemical reactions or otherwise detrimentally affect the catalytic performance of the catalyst. These matrix materials may be particularly troublesome when used in conjunction with relatively highly selective catalysts having sieving properties.
Methanol is readily producible from coal and other raw materials by the use of well-known commercial processes. For example, synthesis gas can be obtained by the combustion of any carbonaceous material including coal or any organic material such as hydrocarbons, carbohydrates and the like. The synthesis gas can be manufactured into methanol by a well known heterogeneous catalytic reaction.
"Hydrocarbons from Methanol" by Clarence D. Chang, published by Marcel Dekker, Inc. N.Y. (1983) presents a survey and summary of the technology described by its title. Chang discussed methanol to olefin conversion in the presence of molecular sieves at pages 21-26. The examples given by Chang as suitable molecular sieves for converting methanol to olefins are chabazite, erionite, and synthetic zeolite ZK-5. The channel dimensions are calculated from a theoretical model.
U.S. Pat. Nos. 4,238,631; 4,328,384; and 4,423,274 disclose processes for converting methanol to olefin-enriched or gasoline boiling range hydrocarbons in the presence of fluid catalyst particles having a zeolite with a pore opening of at least 5 angstroms. These zeolites are distinguished by virtue of having an effective pore size intermediate between the small pore Linde A and the large pore Linde X, i.e., the pore windows of the structure are the size which would be provided by 10 member rings of silicon atoms interconnected by oxygen atoms. These zeolites, which include ZSM-5,ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-38 and ZSM-48. These patents disclose that such intermediate pore size zeolites can be utilized by maintaining a high coke level on the catalyst, in the range of 5 to 20 weight %, to preferentially produce olefins. U.S. Pat. No. 4,079,095 discloses a process for making light olefins from methanol using ZSM-34, which is a zeolite having a pore size somewhat smaller than the zeolites described in the other patents noted in this paragraph. However, no olefin selectivity advantage for maintaining a high coke level was disclosed when using the smaller pore ZSM-34 zeolite.
Among the CMSMs that can be used to promote converting methanol to olefins are non-zeolitic molecular sieves or NZMSs such as aluminophosphate or ALPOs, in particular silicoaluminophosphates or SAPOs disclosed in U.S. Pat. No. 4,440,871. U.S. Pat. No. 4,499,327 issued Feb. 12, 1985, discloses processes for catalytically converting methanol to light olefins using SAPOs at effective process conditions. This U.S. Patent is incorporated in its entirety by reference herein.